<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
  <style>
    body>div{
      width: 200px;
      border: 1px solid #5bbfa3;
      overflow: hidden;
    }
    #d1{
      width: 50px;
      height: 50px;
      background-color: #e7ea84;
      float: left;
    }
    #d2{
      width: 50px;
      height: 50px;
      background-color: #e8e8e8;
      float: right;
    }
    #d3{
      width: 50px;
      height: 50px;
      background-color: gold;
      float: right;
    }
  </style>
</head>
<body>
<div>
  <div id="d1">一</div>
  <div id="d2">二</div>
  <div id="d3">三</div>
</div>
</body>
</html>